All the replies to my post are along the same lines so I'll answer
them all at once :)

My argument was that Assembly language is better than a HLL sometimes,
and hence I only have to prove this is so in at least one case. I am
not saying that online code does not have its place, just that it is
not a replacement for hand-coded ASM in certain cases. Many of the
other optimizations that people have suggested in a software graphics
engine give some performance benefits but do not compare with ASM
coding the inner loop of the rasterizer.